Israel has improved the accuracy of its Arrow 2 missile interceptor system, including its ability to intercept medium-range missiles present in the arsenals of Iran and Syria, media reported on Monday.

The new system, known as "Block 4," will be installed in missile batteries in the coming weeks, reports said.

A security official confirmed to AFP that "improvements were made to Hetz-2," the Arrow system, but declined to elaborate.

Media said the new system will improve accuracy in intercepting medium-range missiles such as Iran's "Shahab" and "Sejil," as well as Scud Ds held by Syria.

The army also has the Iron Dome anti-rocket defence system, capable of intercepting rockets with a range of between four kilometres to 70, which it uses against rockets fired from the Islamist Hamas-controlled Gaza Strip.

An Arrow 3 system is also under development and is expected to be operational within two to three years.

Another system, David's Sling, designed to intercept medium-range missiles, is being developed to complement Israel's entire system of missile defence.

In tests the Arrow has managed to intercept missiles similar to Iran's Shahab system during both day and night, and under all weather conditions.

Washington provided up to 80 percent of the funding for the first-generation Arrow system. Since 1991, its development has been funded equally by the United States and Israel.